Treatment of proteinaceous materials with pyruvic acid or glyoxylic acid to remove peroxides



United States Patent 3,218,234 TREATMENT OF PROTEINACEOUS MATERIALS WITH PYRUVIC ACID 0R GLYOXYLIC ACID TO REMOVE PEROXIDES Hermann Wilmsmann, Heidenreichstrasse 4, Darmstadt, Germany, and Eugen Konrad, Darmstadt, Germany; said Konrad assignor to said Wilmsmann No Drawing. Filed May 13, 1963, Ser. No. 280,107 Claims priority, application Germany, May 17, 1962, W 32,278 9 Claims. (Cl. 16787) The present invention is concerned with a treatment of proteinaceous material and, more particularly, with removing peroxide from proteinaceous material such as human hair or wool, containing the same.

It is well known that hydroperoxides are for-med in proteinaceous fibers upon exposure to ultraviolet radiation or in moist condition. It is also known that after an intentional treatment of such fibers with hydrogen-peroxide, residual hydroperoxide remains in the proteinaceous fiber and this peroxide residue will not be removed even upon intensive rinsing. The hydroperoxides which thus remain in the proteinaceous fibers will cause a certain degree of bleaching of the fibers as well as damage to the fiber structure. The unfavorable effect of residual hydroperoxide on proteinaceous fibers becomes apparent, for instance by bleaching human hair in accordance with the method disclosed in US. Patent 1,750,657. Upon subsequent dyeing of the thus-bleached hair with oxidation dyestuffs or nitroa-minobenzenes, it is generally not possible to achieve uniform dyeing of the hair.

It has been attempted to treat, for instance, hydroperoxide-containing human hair with substances which will destroy hydrogen peroxide, in order to remove the hydrogen peroxide residue or to prevent formation thereof. For this purpose, c-atalase was suggested (Swiss Patent No. 264,760) as well as thiourea, thiosulfates, dithionite, hypophosphite and ascorbic acid. However, application of all of these compounds is connected with certain disadvantages which impede their practical usefulness. Thus, catalase in aqueous solutions is not stable for unlimited periods. Furthermore, due to the large size of the catalase molecule, the same cannot penetrate into the interior of the hair and thus will be effective only at the surface of the proteinaceous fiber. Thiosulfate, dithionite, hypophosphites, and ascorbic acid are effective only in an alkaline .pH range. However, in treating human hair, particularly living human hair, it is frequently necessary and very important to remove the peroxide residue in an acidic pH range, since the treating agent is supposed not only to remove hydrogen peroxide residue but also alkaline residues. This is important, for instance, when the removal of peroxide residue is to be carried out as aftertreatment subsequent to permanent waving, bleaching or hair dyeing. An after-treatment which would lead to the destruction of hydrogen peroxide only in an alkaline pH range would then require a further after-treatment with an acidic agent in order to eliminate alkali residues, and this would considerably prolong the total treating time and make the treatment more expensive.

Of the peroxide destroying agents mentioned so far, only thiourea will also be effective in an acidic pH range and does not have the disadvantages which are characteristic for catalase. For this reason, thiourea is presently extensively used in the treatment of human hair. However, the use of thiourea is frequently unpleasant due to the odor given thereby to the treated hair, as well as due to the unpleasant change in the odor of the thiourea-containing hair treating agent, which is observed not only during treatment but also upon prolonged storage of the treating agent. The cause of this unpleasant odor, i.e.

3,218,234 Patented Nov. 16, 1965 the chemical reactions causing the same, has not yet been completely determined, however, it would appear that probably the sulfur content of the thiourea or its pseudomercaptane characteristics are involved.

In the bleaching of wool with dilute hydrogen peroxide solutions, which bleaching is generally carried out in an alkaline pH range, generally in the presence of sodium pyrophosphate as stabilizing agent, for a period of between 6 and 12 hours and at a temperature of between 40 and 50 C., and in which subsequently acidification is carried out with acids, preferably acetic acid, residual quantities of hydrogen peroxide or peroxide-type bonds will remain in the wool fiber and will have deleterious effect. Therefore the thus-treated wool is frequently further treated with sodium dithionite or similar reducing agents. Since this subsequent reduction with known agents also must be carried out in an alkaline pH range, again a second after-treatment with acidifying agents is required.

It is therefore an object of the present invention to overcome the above-mentioned difficulties and disadvantages in the removal of peroxide from proteinaceous material such as fibers, particularly human hair and wool.

It is a further object of the present invention to provide a method for removing peroxide residue from proteinaceous fibers in an acidic medium.

It is yet another object of the present invention to provide a method for removing peroxide residue from proteinaceous fibers in a simple, quick and effective manner.

Other objects and advantages of the present invention will become apparent from a further reading of the description and of the appended claims.

With the above and other objects in view, the present invention includes a method of treating peroxide-containing proteinaceous material, comprising the step of contacting the material with a substance selected from the group consisting of alpha-carbonyl-monocarboxylic acids of the general formula RCOCOOH, wherein R is selected from the group consisting of hydrogen and alkyls having up to 5 carbon atoms, and salts thereof.

Surprisingly, it has been found that by treating the proteinaceous material, particularly fibers such as hair or wool with an alpha-carbonyl-monocarboxylic acid of the general formula RCOCOOH or salts thereof, whereby R denotes hydrogen or an alkyl, preferably an alkyl with up to five carbon atoms, the above discussed disadvantages and diflic-ulties are overcome.

It is possible to produce stable solutions of these alphacarbonyl-monocarboxylic acids and their soluble salts, which solutions will free not only the surface but also the interior of the proteinaceous fibers from peroxide residues and thus protect the fibers against attack by hydroperoxide. Furthermore, these treating agents are effective in an acidic pH range as well as under alkaline conditions.

Particularly suitable for the purpose of the present invention are :pyruvic acid and glyoxylic acid is well as the wateror alcohol-soluble salts thereof. Thus, according to the present invention, preferably, in addition to these acids, the following salts thereof may be advantageously used: sodium, potassium, ammonium, calcium, magnesium, aluminum salts, as well as organic amines such as monoethanolamine, diethanolamine, triethanolamine, butylamine, isopropanolamine, and trishydroxymethyl-aminomethane salts. However the salts of the heavy metals as well as of barium and strontium are to be excluded.

It may be noted that although it is a particular advantage of the treatment according to the present invention that the same can be carried out in an acidic medium, it is also possible to carry out the removal of peroxide residues from proteinaceous fibers in accordance with the present invention in an alkaline pH range.

The above described reactants or treating agents which are used, according to the present invention, for the removal of peroxide from proteinaceous fibers will react not only with hydrogen peroxide or with substances which free hydrogen peroxide such as carbamide-peroxide, sodium borate-peroxyhydrate, sodium percarbonate or sodium perphosphate, but also with hydroperoxides of the general formula XOOH, whereby X denotes any organic residue or also hydrogen. Thus, according to the present invention, it is possible to remove with alpha-carbonylcarboxylic acids and salts thereof not only the residual peroxide from a hydrogen peroxide treatment, but also such peroxide-type bonds within the proteinaceous fiber which may be formed of hydrogen peroxide and protein. Upon reduction of hydrogen peroxide, pyruvic acid is converted into acetic acid, and glyoxylic acid is transformed into formic acid.

Generally, particularly for removing peroxide residues from human hair, the reactants described above will be applied distributed in suitable carriers, for instance dissolved in water or aqueous alcohol, or in the form of a suitable cream or paste, whereby the concentration of the alpha-monocarboxylic acid or salt preferably will be between 0.5 and 4% by weight, and in most cases between about 1 and 2%. If the free acid is used, then best results will be frequently obtained with a concentration of about 1%, While the salts are preferably used in a concentration of about 2%, whereby all percentage figures are intended to indicate percent by weight.

The reaction products obtained by the reaction of the above-mentioned acids or salts with the peroxide of the proteinaceous fibers are completely harmless substances which, in addition, will cause a desirable acidification of the fibers. Furthermore, the alpha-carbonyl-monocarboxylic acids and their salts which may be used according to the present invention are also capable to react by means of their reactive carbonyl group with SI-I, NHzor peptide groups of the proteinaceous fibers and thereby to cause cross linking or blocking of active groups which in turn will improve the structure and reduce the reactivity of the proteinaceous fibers.

Using the method described by H. Freitag (Z. analyt. Chem. 131, 77 (1950)), it is possible to discover an oxidizing effect of proteinaceous fiber which weeks prior thereto had been treated with hydrogen peroxide. In contrastthereto, if such proteinaceous fibers are subjected to an after-treatment according to the present invention, such oxidizing effect disappears within a few minutes after such treatment.

The alpha-carbonyl-monocarboxylic acids and their soluble salts may be distributed in a carrier substance which after being in contact with the hair or the like for a limited period of time is again removed, preferably by rinsing, or the reactants according to the present invention may also be incorporated in carrier substances which after being applied to, for instance, human hair are not removed therefrom, such as setting agents.

Even hair which has been bleached with persulfate can be uniformly dyed after an intermediate treatment with alpha-carbonyl-monocarboxylic acids or their salts in accordance with the present invention.

The alpha-carbonyl-monocarboxylic acids and their salts which are used according to the present invention may be incorporated in all conventional types of hair treating agents such as aqueous, alcoholic or aqueousalcoholic solutions, emulsions and the like.

The following examples are given as illustrative only of the present invention without, however, limiting the invention to the specific details of the examples.

EXAMPLE I A permanent Wave is applied to living human hair by means of a conventional solution of thioglycolate, fixed in conventional manner with hydrogen peroxide and thereafter the hair is treated for about five minutes with one of the following solutions:

Solution A G. Pyruvic acid and/ or glyoxylic acid 1.0 Perfume oil 0.3

Isopropanol 30.0 Water 87.7

Solution B 2.0 g. of the sodium, potassium, ammonium, calcium,

magnesium, aluminum, monoethanolamine, diethanolamine, triethanolamine, butylamine, isopropanolamine or trishydroxymethyl-amino-methane salt of pyruvic and/ or glyoxylic acid 0.5 g. water-soluble perfume oil 97.5 g. water Solution C 2.0 g. of any of the salts of Solution B 0.5 g. tartaric acid 0.5 g. water-soluble perfume oil 97.0 g. water Solution D 2.0 g. of any of the salts of Solution B 2.0 g. 25% aqueous ammonia 0.3 g. perfume oil 30.0 g. ethanol 64.7 g. water Solution E 1.0 g. pyruvic and/ or glyoxylic acid 0.2 g. laurylpyridinium chloride 0.3 g. perfume oil 40.0 g. isopropanol 58.5 g. Water EXAMPLE II 66.3 g. sodium salt of pyruvic acid 10.0 g. laurylpyridinium chloride 2.7 g. tartaric acid 1.0 g. dry perfume 20.0 g. water-free sodium sulfate are finely ground, mixed and packed in bags of synthetic sheet-material, each bag containing 3 grams of the dry mixture. Shortly before use, a solution is formed by dissolving the contents of one bag in 30 milliliters of lukewarm Water. The thus-formed solution is used as indicated in Example I.

EXAMPLE III EXAMPLE IV Human hair is bleached in conventional manner with potassium persulfate in accordance with the method disclosed in the US. Patent 1,750,657, and thereafter treated with any one of the solutions of Examples I and II. The thus treated hair may now be dyed with a solution of 0.12% 2-nitro-l,4-phenylenediamine and 1% of an aqueous 25% ammonia solution, the balance, i.e. 98.98% being water, and thereby the desired uniform coloration of the dyed hair will be achieved, while similarly bleached hair which has not been subjected to the intermediate treatment according to the present invention, upon dyeing in the above described manner, will be of spotty appearance.

EXAMPLE V Human hair is wetted with a setting agent of the following composition:

2.0 g. polyvinylpyrrolidone 1.0 g. sodium salt of pyruvic acid 0.3 g. tartaric acid 40.0 g. isopropanol 0.3 g. perfume oil 56.4 g. water The hair is then set in the desired shape and dried. After wetting the thus treated hair and even upon exposure to ultra violet rays, it is not possible to determine the presence of hydroperoxide therein.

EXAMPLE VI EXAMPLE VII Raw wool is bleached as described in Example VI, rinsed with water for a short period of time and then treated for several minutes with a 4% aqueous solution of glyoxylic acid. No residual peroxide can be found in the thus-treated wool which is of acidic pH.

EXAMPLE VIII Human hair is wetted with a setting agent as described in Example V, in which the 1.0 g. of the sodium salt of pyruvic acid is replaced by 0.5 g. of pyruvic acid. The hair is then set in the desired shape and dried. After wetting the thus treated hair and even upon exposure to ultra violet rays, it is not possible to determine the presence of hydroperoxide therein.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers with a substance selected from the group consisting of pyruvic acid, glyoxylic acid, and their sodium potassium, ammonium, calcium, magnesium, aluminum and organic amine salts.

2. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with a substance selected a from the group consisting of pyruvic acid, glyoxylic acid, and their sodium, potassium, ammonium, calcium, magnesium, aluminum and organic amine salts.

3. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with a carrier substance compatible with said fibers and having distributed therethrough between about 0.5 and 4% of a substance selected from the group consisting of pyruvic acid, glyoxylic acid, and their sodium, potassium, ammonium, calcium, magnesium, aluminum and organic amine salts.

4. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with an aqueous solution compatible with said fibers and having distributed therethrough between about 0.5 and 4% of a substance selected from the group consisting of pyruvic acid, glyoxylic acid, and their sodium, potassium, ammonium, calcium, magnesium, aluminum and organic amine salts.

5. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with a carrier substance compatible with said fibers and having distributed therethrough between about 1 and 2% of a substance selected from the group consisting of pyruvic acid, glyoxylic acid, and their sodium, potassium, ammonium, calcium, magnesium, aluminum and organic amine salts.

6. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with a carrier substance compatible with said fibers and having distributed therethrough about 1% by weight of a substance selected from the group consisting of pyruvic acid and glyoxylic acid.

7. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers with a carrier substance compatible therewith and having distributed therethrough between about 0.5 and 4% by weight of pyruvic acid.

8. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers with a carrier substance compatible therewith and having distributed therethrough between about 0.5 and 4% by weight of glyoxylic acid.

9. A method of treating peroxide-containing proteinaceous fibers selected from the group consisting of human hair and wool for the removal of peroxide therefrom, comprising the step of contacting said peroxide-containing fibers in an acidic medium with a carrier substance compatible with said fibers and having distributed therethrough about 2% by weight of a substance selected from the group consisting of alkali metal, ammonium, calcium, magnesium, aluminum and organic amino salts of pyruvic acid and glyoxylic acid.

References Cited by the Examiner UNITED STATES PATENTS 1/1917 Anders 16787.l 6/1959 Flesch 16788 OTHER REFERENCES JULIAN S. LEVITT, Primary Examiner.

FRANK CACCIAPAGLIA, JR., LEWIS GOTTS,

Examiners. 

1. A METHOD OF TREATING PEROXIDE-CONTAINING PROTEINACEOUS FIBERS SELECTED FROM THE GROUP CONSISTING OF HUMAN HAIR AND WOOL FOR THE REMOVAL OF PEROXIDE THEREFROM, COMPRISING THE STEP OF CONTACTING SAID PEROXIDE-CONTAINING FIBERS WITH A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF PYUVIC ACID, GLYOXYLIC ACID AND THEIR SODIUM POTASSIUM, AMMONIUM, CALCIUM, MAGNESIUM, ALUMINUM AND ORGANIC AMINE SALTS. 